org.camunda.bpm.application

Class ProcessApplicationContext

java.lang.Object

org.camunda.bpm.application.ProcessApplicationContext

public class ProcessApplicationContext
extends Object

A utility to declare the process application in which subsequent engine API calls are executed. Process application context is important for the engine to access custom classes as well as process-application-level entities like script engines or Spin data formats.

By default, the process engine only guarantees to switch into the context of the process application when it executes custom code (e.g. a JavaDelegate). This utility allows to declare a process application into which the process engine then switches as soon as it begins executing a command. Example using a variable that is serialized with a Camunda Spin data format:

  try {
    ProcessApplicationContext.setCurrentProcessApplication("someProcessApplication");
    runtimeService.setVariable(
      "processInstanceId",
      "variableName",
      Variables.objectValue(anObject).serializationDataFormat(SerializationDataFormats.JSON).create());
  } finally {
    ProcessApplicationContext.clear();
  }
 

Declaring the process application context allows the engine to access the Spin JSON data format as configured in that process application to serialize the object value. Without declaring the context, the global json data format is used.

Declaring the context process application affects only engine API invocations. It DOES NOT affect the context class loader for subsequent code.

Author:

Thorben Lindhauer

Constructor Summary

Constructors

Constructor and Description
ProcessApplicationContext()

Method Summary

Methods

Modifier and Type	Method and Description
static void	clear() Clears the currently declared context process application.
static void	setCurrentProcessApplication(ProcessApplicationInterface processApplication) Declares the context process application for all subsequent engine API invocations until clear() is called.
static void	setCurrentProcessApplication(ProcessApplicationReference reference) Declares the context process application for all subsequent engine API invocations until clear() is called.
static void	setCurrentProcessApplication(String processApplicationName) Declares the context process application for all subsequent engine API invocations until clear() is called.
static <T> T	withProcessApplicationContext(Callable<T> callable, ProcessApplicationInterface processApplication) Takes a callable and executes all engine API invocations within that callable in the context of the given process application
static <T> T	withProcessApplicationContext(Callable<T> callable, ProcessApplicationReference reference) Takes a callable and executes all engine API invocations within that callable in the context of the given process application
static <T> T	withProcessApplicationContext(Callable<T> callable, String processApplicationName) Takes a callable and executes all engine API invocations within that callable in the context of the given process application

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ProcessApplicationContext

public ProcessApplicationContext()

Method Detail

setCurrentProcessApplication

public static void setCurrentProcessApplication(String processApplicationName)

Declares the context process application for all subsequent engine API invocations until clear() is called. The context is bound to the current thread. This method should always be used in a try-finally block to ensure that clear() is called under any circumstances.

Parameters:

processApplicationName - the name of the process application to switch into

setCurrentProcessApplication

public static void setCurrentProcessApplication(ProcessApplicationReference reference)

Declares the context process application for all subsequent engine API invocations until clear() is called. The context is bound to the current thread. This method should always be used in a try-finally block to ensure that clear() is called under any circumstances.

Parameters:

reference - a reference to the process application to switch into

setCurrentProcessApplication

public static void setCurrentProcessApplication(ProcessApplicationInterface processApplication)

Declares the context process application for all subsequent engine API invocations until clear() is called. The context is bound to the current thread. This method should always be used in a try-finally block to ensure that clear() is called under any circumstances.

Parameters:

processApplication - the process application to switch into

clear

public static void clear()

Clears the currently declared context process application.

withProcessApplicationContext

public static <T> T withProcessApplicationContext(Callable<T> callable,
                                  String processApplicationName)
                                       throws Exception

Takes a callable and executes all engine API invocations within that callable in the context of the given process application

Equivalent to

   try {
     ProcessApplicationContext.setCurrentProcessApplication("someProcessApplication");
     callable.call();
   } finally {
     ProcessApplicationContext.clear();
   }
 

Parameters:

callable - the callable to execute

name - the name of the process application to switch into

Throws:

Exception

withProcessApplicationContext

public static <T> T withProcessApplicationContext(Callable<T> callable,
                                  ProcessApplicationReference reference)
                                       throws Exception

Takes a callable and executes all engine API invocations within that callable in the context of the given process application

Equivalent to

   try {
     ProcessApplicationContext.setCurrentProcessApplication("someProcessApplication");
     callable.call();
   } finally {
     ProcessApplicationContext.clear();
   }
 

Parameters:

callable - the callable to execute

reference - a reference of the process application to switch into

Throws:

Exception

withProcessApplicationContext

public static <T> T withProcessApplicationContext(Callable<T> callable,
                                  ProcessApplicationInterface processApplication)
                                       throws Exception

Takes a callable and executes all engine API invocations within that callable in the context of the given process application

Equivalent to

   try {
     ProcessApplicationContext.setCurrentProcessApplication("someProcessApplication");
     callable.call();
   } finally {
     ProcessApplicationContext.clear();
   }
 

Parameters:

callable - the callable to execute

processApplication - the process application to switch into

Throws:

Exception